DETECTION OF STRUCTURES ON MULTIPLE SCALES AROUND THE SOUTH-GALACTIC-POLE - A 2-DIMENSIONAL ANALYSIS OF THE COSMOS UKST-SOUTHERN-SKY-GALAXY-CATALOG/

We report the results of a 2D analysis of distributions of galaxies in a search for structures on a wide range of scales, from clusters up t o superclusters and beyond, including the identification of voids. The structures are identified in data from the COSMOS/UKST Southern Sky G alaxy Catalogue (CUSSGC). The subsample used in this first investigati on contains some 1.4 10(6) galaxies in an area of similar to 69 x 44 d egrees around the South Galactic Pole. From our analysis, we find 25 v ery large-scale structures (of 10 degrees or more in extent), about 60 structures of intermediate scales (superclusters and/or elongated fea tures), and more than 220 cluster-sized objects. All these features ar e significant, having high confidence levels for detection. Some exten ded voids are also detected in this area, likewise with high significa nce. This work is based on the use of the wavelet transform, the metho d of which has already been extensively described in a previous paper in which we demonstrated the principle of the technique. The wavelet a nalysis gives the position of the structures detected, together with s ignificance levels and some parametrisation of their properties (exten t, population, elongation, etc). Ultimately, our aim is the constructi on of a. large and homogeneous database of structures on all scales in this important part of the southern sky.